[PATCHv5 2/2] driver: serial: omap: prevent runtime PM for "no_console_suspend"
From: Sourav Poddar <hidden>
Date: 2013-04-26 20:05:14
Also in:
linux-omap, linux-serial
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
The driver manages "no_console_suspend" by preventing runtime PM during the suspend path, which forces the console UART to stay awake. Signed-off-by: Sourav Poddar <redacted> Reviewed-by: Felipe Balbi <redacted> --- drivers/tty/serial/omap-serial.c | 34 +++++++++++++++++++++++++++++++++- 1 files changed, 33 insertions(+), 1 deletions(-)
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 30d4f7a..9457fe3 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c@@ -161,6 +161,7 @@ struct uart_omap_port { u32 calc_latency; struct work_struct qos_work; struct pinctrl *pins; + bool is_suspending; }; #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
@@ -1312,6 +1313,22 @@ static struct uart_driver serial_omap_reg = { }; #ifdef CONFIG_PM_SLEEP +static int serial_omap_prepare(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + up->is_suspending = true; + + return 0; +} + +static void serial_omap_complete(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + up->is_suspending = false; +} + static int serial_omap_suspend(struct device *dev) { struct uart_omap_port *up = dev_get_drvdata(dev);
@@ -1330,7 +1347,10 @@ static int serial_omap_resume(struct device *dev) return 0; } -#endif +#else +#define serial_omap_prepare NULL +#define serial_omap_prepare NULL +#endif /* CONFIG_PM_SLEEP */ static void omap_serial_fill_features_erratas(struct uart_omap_port *up) {
@@ -1616,6 +1636,16 @@ static int serial_omap_runtime_suspend(struct device *dev) struct uart_omap_port *up = dev_get_drvdata(dev); struct omap_uart_port_info *pdata = dev->platform_data; + /* + * When using 'no_console_suspend', the console UART must not be + * suspended. Since driver suspend is managed by runtime suspend, + * preventing runtime suspend (by returning error) will keep device + * active during suspend. + */ + if (up->is_suspending && !console_suspend_enabled && + uart_console(&up->port)) + return -EBUSY; + if (!up) return -EINVAL;
@@ -1666,6 +1696,8 @@ static const struct dev_pm_ops serial_omap_dev_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume) SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend, serial_omap_runtime_resume, NULL) + .prepare = serial_omap_prepare, + .complete = serial_omap_complete, }; #if defined(CONFIG_OF)
--
1.7.1